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Re: Topband: Verticals on the beach

To: Stan Stockton <wa5rtg@gmail.com>
Subject: Re: Topband: Verticals on the beach
From: Dan Maguire via Topband <topband@contesting.com>
Reply-to: Dan Maguire <djm2150@yahoo.com>
Date: Fri, 30 Dec 2022 22:06:32 +0000 (UTC)
List-post: <mailto:topband@contesting.com>
 Stan Stockton wrote:
>>> Specifically what I want to find out is how much louder I would likely be 
>>> in Europe from 25 degrees to 50 degrees if the vertical was on that line 
>>> you drew as compared to being 70 feet below the line.

>>> Can AutoEZ be used to model this?

Yes, but only assuming that the water's edge is a straight line parallel to the 
Y axis. Here's a comparison of the azimuth patterns at a 10° elevation angle 
when a) the vertical is right at the water's edge and b) the vertical is 70 
feet back from the water. Land is to the left of the Y axis and water is to the 
right.

https://i.postimg.cc/j5RDRMGz/image.png

The green dot marker is at 5° "into the water" since the water's edge is along 
the up/down Y axis. At that azimuth there is a 5.3 dB advantage to having the 
vertical at the water's edge. In contrast, looking straight out over the water 
(along the X axis) the advantage of being at the edge is only 0.8 dB.

In the image above, a second set of azimuth ring labels (in parenthesis) has 
been added. This "compass rose" set of labels will help to mentally rotate the 
entire chart such that the water's edge (the Y axis) aligns with your physical 
location. Here's another image explaining that second set of labels.

https://i.postimg.cc/zfrBkdD9/image.png

Dan, AC6LA  
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